
Aledo
- County:
- Mercer County
- County Seat:
- Yes
- Area (mi²):
- 2.344
- State:
- Illinois
Aledo is a city located in Mercer County, Illinois. Aledo has a 2025 population of 3,536. It is also the county seat of Mercer County. Aledo is currently declining at a rate of -0.45% annually and its population has decreased by -2.27% since the most recent census, which recorded a population of 3,618 in 2020.
The average household income in Aledo is $81,034 with a poverty rate of 10.24%. The median age in Aledo is 40.7 years: 38.6 years for males, and 42.4 years for females.